package com.example.demo.Fileter;
import com.example.demo.pojo.LoginUser;
import com.example.demo.pojo.SysUser;
import com.example.demo.uilt.JwtUtil;
import com.example.demo.uilt.RedisCache;
import io.jsonwebtoken.Claims;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.filter.OncePerRequestFilter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Objects;


@Component
public class JwtAuthenticationTokenFilerter extends OncePerRequestFilter {

  @Autowired
  private RedisCache redisCache;

  @Override
  protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
    //获取token
    String token = request.getHeader("token");

    if (!StringUtils.hasText(token)) {
      //请求没有携带token就放行
      filterChain.doFilter(request, response);
      return;
    }
    // 有token才解析
    Claims claims = null;
    try {
      claims = JwtUtil.parseJWT(token);
    } catch (Exception e) {
      throw new RuntimeException("token非法");
    }

    // 获取 userId
    String userId = claims.getSubject();
    // 去redis中获取用户信息
    LoginUser loginUser = redisCache.getCacheObject("login:" + userId);
    // loginUser为空 说明 未登录
    if(Objects.isNull(loginUser)){
      throw new RuntimeException("用户未登录");
    }

    // 如果存在，则把用户信息 存到 SecurityContextHolder 对象中
    // todo 补充权限信息
    UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(loginUser,null,loginUser.getAuthorities());
    SecurityContextHolder.getContext().setAuthentication(authenticationToken);

    // 放行
    filterChain.doFilter(request, response);
  }

}